1. Field of the Invention
The present invention relates to a rivet gun, and more particularly to a rivet gun that has a handle connected detachably to a cylinder. Therefore, the cylinder may be replaced by another cylinder of a different size or type.
2. Description of Related Art
A conventional rivet gun, as disclosed by Taiwan utility model patent No. M400369, is used to rivet two boards such that the boards are securely mounted together by rivets. A rivet has a cap and a core pin. The cap is T-shaped and has an enlarged end and a mounting end. The core pin is mounted longitudinally through and protrudes out of the cap and has two ends and a ball formed on one end and adjacent to the mounting end of the cap.
A conventional rivet gun comprises a barrel, a handle, a trigger, a pin collector and a pneumatic cylinder.
The barrel has a front end, a rear end and a vise assembly that may vise and pull a core pin of a rivet on the front end into the barrel. The handle is mounted perpendicularly on the barrel and has air passageways. The collector is a jar mounted on the rear end of the barrel to collect the ejected core pins. The pneumatic cylinder is mounted movably under the handle and capable of activating the vise assembly through pneumatic and hydraulic means. Furthermore, the pneumatic cylinder may be connected to a high-pressure air source such as an air bottle to implement the ejection of the core pin.
When the rivet gun is used to rivet two pieces such as boards or plates together, a rivet is mounted through the pieces. The enlarged end of the cap of the rivet abuts an inside piece and the front end of the barrel of the rivet gun abuts the enlarged end. The trigger is pulled to activate the vise assembly to pull a core pin on the cap into the barrel. The ball on the core pin longitudinally compresses and radially expands the mounting end of the cap into T-shape so that the expanded mounting end hooks on an outside piece to complete the riveting process. Then, the air output by the high-pressure air source flows through the barrel from the front end to the rear end and sucks the broken core pin vised by the vise assembly backward into the collector.
The bottom of the handle has a flange formed thereon and having a stepped mounting slot formed on a bottom surface of the flange. The pneumatic cylinder has a hollow and annular body and a top cover screwed on a top end of the annular body and having a stepped protrusion formed on the top cover and mounted in the stepped slot of the flange. Therefore, the top cover of the pneumatic cylinder is covered and enclosed by the flange on the bottom of the handle. However, the size of the enclosed top cover of the pneumatic cylinder is limited by the flange of the handle and the annular body such that the size of the annular body corresponding to the top cover is also limited. As a result, the flange of the handle only fits one pneumatic cylinder with a specific size instead of matching pneumatic cylinders with different sizes.
To overcome the shortcomings, the present invention provides a rivet gun with a changeable cylinder to mitigate or obviate the aforementioned problems.